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        <PersonNm>Kevin Churchwell MD</PersonNm>
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        <PersonNm>Sandra Fenwick</PersonNm>
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      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>Doug Vanderslice</PersonNm>
        <TitleTxt>Treasurer &amp; Trustee</TitleTxt>
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      <RltdOrgOfficerTrstKeyEmplGrp>
        <PersonNm>Michele Garvin Esq</PersonNm>
        <TitleTxt>Secretary &amp; Trustee</TitleTxt>
        <BaseCompensationFilingOrgAmt>0</BaseCompensationFilingOrgAmt>
        <CompensationBasedOnRltdOrgsAmt>644253</CompensationBasedOnRltdOrgsAmt>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 4b</FormAndLineReferenceDesc>
        <ExplanationTxt>Children's Hospital Corporation, a related organization, made contributions to the supplemental non-qualified retirement plan for the individuals listed below. Contributions are generally based on a percentage of compensation. Participants of the supplemental executive retirement plan are fully vested. All payments with respect to a participant's separation from service will be made in a single sum following the separation from service unless participant has elected to receive the accrued interest portion of his or her account in three annual installments. Contributions were for Children's Hospital Corporation employee benefits and not for Blood Research Institute, Inc. Trustee or Officer of the Board services and/or responsibilities. Kevin Churchwell, received in 2020, a contribution of $301,500 Sandra Fenwick, received in 2020, a contribution of $539,500 Michele Garvin, received in 2020, a contribution of $97,680 Doug Vanderslice, received in 2020, a contribution of $229,480</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part II:</FormAndLineReferenceDesc>
        <ExplanationTxt>Compensation is for Children's Hospital Corporation executive/employee services; not for Blood Research Institute, Inc. Trustee or Officer of the Board services.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleJ>
    <IRS990ScheduleO documentId="RetDoc1044400001">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 6</FormAndLineReferenceDesc>
        <ExplanationTxt>Children's Medical Center Corporation is the sole Member of Blood Research Institute.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7a</FormAndLineReferenceDesc>
        <ExplanationTxt>Children's Medical Center Corporation, as the sole Member of Blood Research Institute, elects the governing body of the Organization.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section A, line 7b</FormAndLineReferenceDesc>
        <ExplanationTxt>Children's Medical Center Corporation is the sole Member of Blood Research Institute and has the right to elect directors and other powers and rights as vested in them by law, the articles of organization or the By-Laws of the organization.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 11b</FormAndLineReferenceDesc>
        <ExplanationTxt>The 990 was prepared by the staff of the Children's Hospital Corporation. The 990 was then provided to the Treasurer for review.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 12</FormAndLineReferenceDesc>
        <ExplanationTxt>Currently Blood Research Institute, Inc. has no conflict of interest policy. The Officers and Trustees of Blood Research Institute are also Officers and Trustees of the sole member, Children's Medical Center Corporation, and annually discloses any conflicts of interest under the Children's Medical Center Corporation's conflict of interest policy.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section B, line 15</FormAndLineReferenceDesc>
        <ExplanationTxt>Blood Research Institute, Inc. does not have any employees and does not compensate its Trustees or Officers of the Board.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part VI, Section C, line 19</FormAndLineReferenceDesc>
        <ExplanationTxt>The Organization's governing documents, audited financial statements, and Form 990 are available upon request. The Organization's Form 990 is also available at the website of Massachusetts' Attorney General.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990, Part I, Line 4 and VI, Line 1b - Governing Body &amp; Management</FormAndLineReferenceDesc>
        <ExplanationTxt>The filing organization has one independent member of the governing body. The other members of the governing body are compensated by a related organization. However, the filing organization is part of an integrated delivery system of organizations, including Children's Hospital that has community boards.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
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        <DisregardedEntityName>
          <BusinessNameLine1Txt>Children's Medical Center Corporation</BusinessNameLine1Txt>
        </DisregardedEntityName>
        <USAddress>
          <AddressLine1Txt>300 Longwood Avenue</AddressLine1Txt>
          <CityNm>Boston</CityNm>
          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>02115</ZIPCd>
        </USAddress>
        <EIN>041174680</EIN>
        <PrimaryActivitiesTxt>Holds &amp; manages securities &amp; real estate investments for subsidiaries</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
        <ExemptCodeSectionTxt>501(c)(3)</ExemptCodeSectionTxt>
        <PublicCharityStatusTxt>Line 12c, III-FI</PublicCharityStatusTxt>
        <DirectControllingNACd>N/A</DirectControllingNACd>
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        </USAddress>
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        <PrimaryActivitiesTxt>Pediatric Teaching and Research Hospital</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
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          <StateAbbreviationCd>MA</StateAbbreviationCd>
          <ZIPCd>02115</ZIPCd>
        </USAddress>
        <EIN>043323330</EIN>
        <PrimaryActivitiesTxt>Holds &amp; manages satellite ambulatory centers; real estate investments</PrimaryActivitiesTxt>
        <LegalDomicileStateCd>MA</LegalDomicileStateCd>
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        <PublicCharityStatusTxt>Line 10</PublicCharityStatusTxt>
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          <StateAbbreviationCd>MA</StateAbbreviationCd>
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</Return>
